After Effects can't find QuickTime.

One day I did a disk clean-up, and ever since then, after effects can't find QuickTime. I get a warning message at the startup saying that QuickTime isn't installed. I have reinstalled both after effects and QuickTime and reset both of their preferences. Nothing seems to work. If you have a solution, PLEASE tell me. I am so desperate to get after effects working again. I have been dealing with weeks of frustration over this issue. Any help would be appreciated